Computer systems are becoming increasingly pervasive in our society, including everything from small handheld electronic devices, such as personal data assistants and cellular phones, to application-specific electronic devices, such as set-top boxes, digital cameras, and other consumer electronics, to medium-sized mobile systems such as notebook, sub-notebook, and tablet computers, to desktop systems, workstations, and servers. Computer systems typically include one or more processors. A processor manipulates and controls the flow of data in a computer by executing instructions. To provide more powerful computer systems for consumers, processor designers strive to continually increase the operating speed of the processor. Unfortunately, as processor speed increases, the power consumed by the processor tends to increase as well. Historically, the power consumed by a computer system has been limited by two factors. First, as power consumption increases, the computer tends to run hotter, leading to thermal dissipation problems. Second, the power consumed by a computer system may tax the limits of the power supply used to keep the system operational, reducing battery life in mobile systems and diminishing reliability while increasing cost in larger systems.
One method of reducing the amount of electric power drawn by a computer system is to design the system such that it is capable of operating in two different states. In a first state of operation, only the most vital functions of the system, such as those dedicated to monitoring for user input, are active. This may be referred to as a “sleep state.” During the sleep state, the computer system draws very little power from the voltage regulator (alternatively referred to as the power supply/source, voltage supply/source, or Vcc supply/source). In a second state of operation, the computer system is busy executing instructions to accomplish a particular task. This is referred to as the “wake state.” During the wake state, the computer system consumes a significant amount of power from the power supply.
Unfortunately, a voltage regulator may be designed to operate more efficiently during a wake state than during a sleep state, resulting in poor average power ED consumption over an extended period of time.
The present invention addresses this and other issues associated with the prior art.